A search engine is a tool that identifies documents, typically stored on hosts distributed over a network, which satisfy search queries specified by users. Web search engines work by storing information about a large number of documents (such as web pages) which they retrieve from the World Wide Web (WWW) via a web crawler. Such documents are downloaded by the web crawlers during crawling sessions for purposes of indexing. However, some websites may have several owners. Valid owners of a website may be authorized to perform certain functions for the website Thus, it may be advantageous to periodically re-verify ownership rights with respect to the website.
Like reference numerals refer to corresponding parts throughout the drawings.